Vane pump



Oct. 11, 1960 A. w. GAUBATZ 2,955,542

VANE PUMP 5 Sheets-Sheet 1 Filed Sept. 23, 1959 Oct. 11, 1960 A. w. GAUBATZ 2,955,542

VANE PUMP Filed Sept. 23, 1959 5 Sheets-Sheet 2 IN V EN TOR.

A TT'OENE) Oct. 11, 1960 A. w. GAUBATZ 2,955,542

VANE PUMP Filed Sept. 23, 1959 5 Sheets-Sheet s Oct. 11, 1960 A. w. GAUBATZ 2,955,542

' VANE PUMP Filed Sept. 23, 1959 5 Sheets-Sheet 4 IN V EN TOR.

By (7f/Jzzr% $4 5052 AQFW A TTOE/VEY Oct. 11, 1960 Filed Sept. 23, 1959 IN VEN T OR.

ATTORNEV Patented Oct. 11, 1960 VANE PUMP 7 Filed Sept. 23, 1959, Ser. No. 841,793

6 Claims. (Cl. 103-120) The present invention relates to an improved variable capacity vane type pump. More specifically the present pump includes improved porting and sealing arrangements whereby pump efliciency and operation is greatly improved.

In order to achieve high pump efliciency, it is necessary to avoid leakage betweenthe faces of the pump port plates and the rotor as Well as between the pump vanes and the adjustable outer ring. These leakage paths exist at each side of the rotor and are, therefore, very long requiring a careful job ofsealing which must be accomplished while still maintaining free motion of the ring for eccentricity adjustment and freedom of rotation for the rotor and its vanes. The rotor must, of course, be just slightly narrower than the outer ring for free rotation and the vanes slightly looser than the rotor to assure free sliding of the vanes in the rotor slots as well as along the faces of the port plates.

In the present invention a unique spring and pressure sealing arrangement is utilized in which the high pressure ports are sealed in a way to substantially eliminate the leakage noted and thereby to increase pump efficiency.

Additionally the present pump design results in increased efficiency as a result of the unique port arrangement which permits decreased port velocity.

The details as well as other objects and advantages of the present invention will be apparent from a perusal of the detailed description which follows.

In the drawings:

Figure l is a sectioned side elevational View of the subject pump; 1

Figure 2 is a view along line 2-2 of Figure 1;

Figure 2a is a fragmentary enlargement from Figure 2;

Figures 3-5 are views of the pump rotor;

Figures 6-8 are views of one of the port plates; and Figure 9 is a view along line 9-9 of Figure 1. Referring to Figures 1 and 2 of the drawings, a variable capacity vane pump is indicated generally at 10. Pump 10 includes casing members 12 and 14 which enclose port plates 16, adjustable outer ring 18, rotor 20, vanes 22 and rotor driving shaft 24. Casing 14 encloses the operating parts of the pump with casing '12 functioning mainly as an end plate or closure.

Casing 14 includes a recessed portion 26 withinwhich a member 28 is slidably disposed. Member 28 is suitably slotted to receive adjustable ring 18 which is main tained within the semi-circular slot by the fluid pressure between the ring and rot-or 20. Adjusting screws 30 and 312 are provided in cap plates 34 and 36 attached to casing 14 and are adapted to extend within casing recess 26.

To change the pumping capacity of pump 10 the eccen- 1, whereby the eccentricity of ring 18 is reduced. In order to approximately position outer ring 18, an additional adjustable screw member 38 is provided. A small clearance is provided between screw 38 and ring 18 to'allow free adjustment by member 28.

While the pump capacity has been shown to be manually adjustable through the use of screws 30 and 32, it should also be noted that such capacity may be automatically varied in accordance with any predetermined operating condition, e.g., pump output pressure, as is well known in the art. As thus far described, pump 10 is of conventional design.

Referring to Figure 2, a fluid inlet is provided at 40 and includes an annular inlet chamber at 42. Input or rotor shaft 24 is supported within casings 12 and 14 through suitable bearing and seal devices indicated generally at 44 and 46.

Referring now to Figures 3 through 5, rotor 20 will be seen to include a plurality of radially extending grooves or slots 48 which open axially and are adapted to slidably receive vanes 22. An enlarged portion '50 is formed at the radially inner ends of grooves 48. By means subsequently to be considered, each groove portion or chamber 50 is adapted to receive pump output pressure to urge vanes 22 radially outwardly into engagement with outer ring 18. In this way leakage between vanes 22 and ring 18 is substantially eliminated by a pressure force which is proportional to pump output pressure.

As best seen in Figure 4, the rotor portions 52 between adjacent vane grooves 48 are angularly notched or tapered at 54. The angular notching of the rotor constitutes an important aspect of the present invention. The angular notches 54 on each side of the rotor and between each vane slot increase the opening available for fluid flow from the inlet port plate opening to fill the increasing volume of the space between adjacent vanes and the outer ring during the suction or fluid intake part of the rotation of the rotor and similarly increases this volume during the discharge portion of rotor rotation. By virtue of increasing the port area through notches 54, the instantaneous suction and discharge velocities of the fluid are very low proximate the rotor and vanes. Such low velocities are essential when hot, low boiling point fuels or cryogenic fluids are being pumped.

Port plates 16 are mirror images of each other, therefore, it will only be necessary to describe one of these in detail. Referring to Figures. 6 through 8, port plate 16 includes an inner face 56 adapted to be disposed in radially abutting relation to outer ring 18, vanes 22 and rotor 20. Plate 16 also includes an outer face 58 adapted to abuttingly engage the face 60 of casing 14. Arcuate dis charge and inlet openings are shown respectively at 62 and 64 in the inner face 56 of the port plate. Discharge opening 62 communicates through a plurality of axially extending upwardly inclined ports 66 terminating in the outer'face 58 of theport plate. Ports 66 in turn communicate with casing discharge passage 67. Similarly, intake opening 64 communicates with the outer face of the port plate through ports 68. Thus, as rotor 20 and vanes 22 are rotated in a clockwise direction as viewed in Figure 1, the progressively increasing volume defined between vanes and outer ring 18 will cause fluid to be drawn in through intake ports 68 to intake opening 64 where it will be entrapped between the vanes and ring. Thereafter, as each adjacent set of vanes passes over bottom deadcenter, indicated generally at 70 in Figure 1,

the cross-over point is reached in which the fluid volume As already noted, it is necessary to urge vanes 22 radially outwardly with a force proportional to the pump discharge pressure in order to eliminate leakage between vanes and ring 18. As already noted, this'is achieved by communicating pump discharge pressure to the enlarged chambers 54) formed at the radially inner end of the vane supporting grooves 48 in the rotor. In order to introduce pump discharge pressure to rotor-chambers 50, an arcuate groove 72 is formed in inner 'face'56 of port plate 16. Grooves 72 and 74 are adapted to be axially aligned with rotor chambers 50. As best seen in Figure 6, grooves 72 and 74 respectively communicate with discharge and intake ports 66 and:68 'Thus the rotor chambers communicating with'groove 72' will be subject to'fluid discharge pressure while the rotor chambers communicating with groove 74 will be subjected to fluid intake pressure. In this way the vanes in the discharge area of the pump will be urged radially outwardly with a greater force than will the vanes in the suction or intake part of the pump. This comports with the necessities of the situation since it would create undue frictional losses to urge all of the vanes radially outwardly into engagement with ring 18 with the same force during dischargeas during the suctional intake stroke when leakage past the end of the vanes is a lesser problem during the latter period of operation.

Leakage between the inner and outer faces 56 and 58 of port plates 16 also presents a serious problem. The means whereby this leakage is prevented will now be described.

Referring again to Figures 2 and 6 through 8, a pressure loading system will be described which substantially eliminates leakage along faces 56 and 58 of the port plates. Inner surface 56 of port plate 16 is provided with an O-ring groove 76 into which an O-ring 78, a back-up washer 80 and a wavy spring washer 82 are placed so that the O-ring with its back-up washer are continually urged against outer ring 18 to effect a complete seal around the circumference of the port plate. It is necessary that the center section of the pump casing 14 have a height which is only slightly greater than the combined height of the two port plates 16 and outer ring 18. This will allow the outer ring 18 to slide freely to affect the eccentricity adjustment and yet not allow O-ring 78 to be blown out through the joint opening between the port plates 16 and ring 18.

On the inner face 56 of port plate 16 an 'area bounded by thepressure opening 62 and extending some distance inward and outward from the opening is subjected to delivery or output pressure which urges the port plate away from rotor 20. This outward load is slightly overbalanced inwardly by an inward acting force produced by delivery or output pressure acting on an area bounded by a kidney-shaped seal indicated generally at 84 in Figure 9, on the outer Surface 58 of port plate and surrounding the pressure ports 66. The kidney-shaped seal 84 includes a groove 86, best shown in Figure 7, within which an O-ring 88, backing washer 90, and a kidneyshaped wavy spring washer 92 are disposed. The kidneyshaped wavy washer 92 is preloaded to a slightly greater value than the inner seal wavy spring Washer 82.

A crescent-shaped groove 94 is also formed in outer face 58 of port plate 16 and has a crescent-shaped wavy spring 96 disposed therein to prevent cocking of plate 16 and hence prevent uneven wear.

The result of this pressure seal and spring construction is that under static-no pressure conditions, port plate 16 is urged inwardly by springs 92 and 96 to seal the plate against rotor 20 and ring 18. When hydraulic pressure is produced a slightly additional inward force is imposed due to the greater outer sealed pressure area compared to the inner pressure port area. This area differential may best be seen in Figure 7 when the outer face kidney-shaped area encompassed by seal-84 is compared with the area of inner face arcuate discharge opening 62 shown in dotted lines. This port plate construction results in complete pressure sealing against leakage of the inner face 56 of port plate 16 due to the effect of both spring load and a controlled hydraulic load.

Inasmuch as the present pump is primarily designed for high speed operation, it is imperative that the inlet and outlet porting be carefully and accurately arranged. In the process of thus arranging the ports various operating conditions 'must be taken into consideration. To avoid lock-up of incompressible fluid, it is necessary to make the cut-off points of the inner and outer inlet ports and openings 68 and 64 as well as the inner and outer discharge ports 62 and 66 as near as possible to the upper and lower dead center. The upper and lower dead centers are indicated generally at 98 and 70 as best seen in Figures 1 and 8.

Further, the adjacent ends of inlet and discharge openings 64 and 62 are spaced apart a distance slightly greater than the distance between adjacent vanes in order to maintain a definite fluid seal. Also, the inlet and discharge openings are timed so that at the cross-over point from pressure to suction, hydraulic force is applied to the inner end of the vane to hold it-upward to maintain a seal at its outer end, supra. Further, and as best seen in Figure 8, it is to be noted that the arcuate length of vane high pressure supplying'groove 72 is greater than that of low pressure supplying groove 74 with the result that pump discharge pressure is maintained on the vanes just before passing bottom dead center 70and just after passing upper dead center 98. In this way a good radial seal is maintained to prevent leakage between vanes 22 and the ring 18.

I claim:

1. A variable capacity pump comprising casing means, fluid inlet and outlet chambers formed in said casing means, a shaft mounted for rotation within said casing means, a' rotor fixed for rotation upon said shaft, 21 plurality of radially extending grooves formed in said rotor and terminating at their outer ends in the peripheral surface of said rotor, a plurality of vane members slidably mounted within said rotor grooves, a ring surrounding said rotor and adapted to be engaged by said vanes to define a fluid pumping chamber intermediate adjacent vanes, said ring being movable from a concentric relationship with said shaft and rotor through a range of eccentric positions, means disposed within said casing means for adjusting the eccentricity of said ring, and a pair of port plates concentrically mounted with respect to said shaft and disposed on opposite sides of said rotor, each of said plates including an inner face abuttingly engaging the radial faces of said rotor, said vanes and said ring, each of said port plates including an outer face abuttingly engaging inner walls of said casing means, each of said port plates including fluid intake and discharge openings formed in the inner face thereof and adapted to communicate with the space between adjacent rotor vanes, said discharge openings communicating with discharge ports in the outer face of said plate, said discharge ports communicating with the discharge opening formed in said casing means, an annular groove formed in each of said port plates adjacent said ring, an O-ring seal disposed in said groove, a backing washer for said O-ring disposed in said groove, and a spring washer disposed in said groove and adapted to abut said backing plate to urge the O-ring into sealing relationshipwith said ring, a continuous groove formed in the outer face of each port plate and surrounding only said discharge ports, an O-ring seal disposed within said outer face'groove, a backing washer disposed in said groove and a spring washer disposed in said outer face groove abuttingly engaging said backing washer to urge the O-ring seal into engagement with the adjacent inner wall of said casing means, said outer face groove spring washer being preloaded to a.greater extent than said inner face groove spring washer whereby the inner face of the portplate is urged into engagement with the adjacent radial faces of said ring, vanesfan'd rotor.

2. A variable capacity pump comprising casing means, fluid inlet and outlet chambers formed in said casing means, a shaft mounted for rotation within said casing means, a rotor fixed for rotation upon said shaft, a plurality of radially extending grooves formed in said rotor and terminating at their outer ends in the peripheral surface of said rotor, a plurality of vane members slidably mounted within said rotor grooves, a ring surrounding said rotor and adapted to be engaged by said vanes to define a fluid pumping chamber intermediate adjacent vanes, said ring being movable from a concentric relationship with said shaft and rotor through a range of eccentric positions, means disposed within said casing means for adjusting the eccentricity of said ring, and a pair of port plates concentrically mounted with respect to said shaft and disposed on opposite sides of said rotor, each of said plates including an inner face abuttingly engaging the radial faces of said rotor, said vanes and said ring, each of said port plates including an outer face abuttingly engaging inner walls of said casing means, each of said port plates including fluid intake and discharge openings formed in the inner face thereof and adapted to communicate with the space between adjacent rotor vanes, said discharge openings communicating with discharge ports in the outer face of said plate, said discharge ports communicating with the discharge opening formed in said casing means, an annular groove formed in each of said port plates adjacent said ring, an O-ring seal disposed in said groove, a backing washer for said O-ring disposed in said groove, and a spring washer disposed in said groove and adapted to abut said backing plate to urge the O-ring into sealing relationship with said ring, a continuous groove formed in the outer face of each port plate and surrounding only said discharge ports, an O-ring seal disposed within said outer face groove, a backing Washer disposed in said groove and a spring washer disposed in said outer face groove abuttingly engaging and backing washer to urge the O-ring seal into engagement with the adjacent inner wall of said casing means, said outer face groove spring Washer being preloaded to a greater extent than said inner face groove spring washer whereby the inner face of the port plate is urged into engagement with the adjacent radial faces of said ring, vanes, and rotor, and a second discontinuous groove formed in the outer face of each plate and a spring washer disposed in said discontinuous groove so as to bias against the adjacent inner Wall of said casing means whereby the inner face of the port plate is urged into engagement with said ring, vanes, and rotor by substantially balanced axial forces.

3. A variable capacity pump as set forth in claim 1 in which the area proscribed by the continuous groove and seal in the outer face of each port plate is greater than the discharge opening area in the inner face of each port plate enabling pump discharge pressure to urge each port plate axially into sealing engagement with the rotor, vanes and ring.

4. A variable capacity pump as set forth in claim 2 in which the area proscribed by the continuous groove and seal in the outer face of each port plate is greater than the discharge opening area in the inner face of each port plate enabling pump discharge pressure to urge each port plate axially into sealing engagement with the rotor, vanes and ring.

5. A variable capacity pump comprising casing means, fluid inlet and outlet chambers formed in said casing means, a shaft mounted for rotation within said casing means, a rotor fixed for rotation upon said shaft, a plurality of radially extending grooves formed in said rotor and terminating at their outer ends in the peripheral surface of said rotor, a plurality of vane members slidably mounted within said rotor grooves, a ring surrounding said rotor and adapted to be engaged by said vanes so as to define a fluid pumping chamber intermediate adjacent vanes, said ring being movable from a concentric relationship with said shaft and rotor through a range of eccentric positions, means disposed within said casing means for adjusting the eccentricity of said ring, and a pair of port plates concentrically mounted with respect to' said shaft and disposed on opposite sides of said rotor, each of said plates including an inner face abuttingly engaging the radial faces of said rotor, said vanes and said ring, each of said port plates including an outer face abuttingly engaging inner walls of said casing means, each of said port plates including fluid inlet and discharge openings formed in the inner face thereof and adapted to communicate with the space between adjacent rotor vanes, said inlet and discharge openings respectively communicating with inlet and discharge ports in the outer face of said plate, said discharge ports communicating with the discharge opening formed in said casing means, an annular groove formed in each of said port plates adjacent said ring and radially outwardly spaced from the vanes, an O-ring seal disposed in said groove, a backing washer for said O-ring disposed in said groove, and a spring Washer disposed in said groove and adapted to abut said backing plate to urge the O-ring into sealing relationship with said ring, a continuous groove formed in the outer face of each port plate and surrounding only said discharge ports, an O-ring seal disposed within said outer face groove, a backing washer disposed in said groove and a spring washer disposed in said outer face groove abuttingly engaging said backing washer to urge the O-ring seal into engagement with the adjacent inner wall of said casing means, said outer face groove spring washer being preloaded to a greater extent than said inner face groove spring Washer whereby the inner face of the port plate is urged into engagement with the adjacent radial faces of said ring, vanes, and rotor, and a second discontinuous groove formed in the outer face of each plate adjacent the inlet ports and a spring washer disposed in said discontinuous groove so as to coact with the continuous groove spring washer in biasing against the adjacent inner wall of said casing means to urge the inner face of the port plate into engagement with said ring, vanes, and rotor by substantially balanced axial forces.

6. A variable capacity pump as set forth in claim 1 in which the rotor portion between adjacent vane grooves is tapered inwardly from each radial face and terminates in the rotor periphery.

References Cited in the file of this patent UNITED STATES PATENTS Re. 22,159 Centervall Aug. 18, 1942 1,223,734 Rinehart Apr. 24, 1917 1,737,942 Pagel -Q Dec. 3, 1929 1,779,757 Streckert Oct. 28, 1930 2,318,292 Chandler May 4, 1943 2,318,337 Schlosser May 4, 1943 2,570,411 Vickers Oct. 9, 1951 2,612,114 Ernst Sept. 30, 1952 2,649,737 Hoen et a1. Aug. 25, 1953 2,708,884 Deschamps May 24, 1955 2,716,946 Hardy Sept. 6, 1955 2,880,678 Hoifer Apr. 7, 1959 FOREIGN PATENTS 221,740 Great Britain Sept. 18, 1924 OTHER REFERENCES German application UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent No., 2,955,542

October 11, 1960 Arthur W, Ga-ubatz It is hereby certified that error a ent requiring correction and that the sa corrected below.

ppears in the above numbered patid Letters Patent should read as Column 5,- line 38, for ."and" read said Signed and sealed this 9th day of May 1961i,"

(SEAL) Attest:

ERNEST W, SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents 

